Traverse mechanism useful in textile machines

ABSTRACT

Traverse mechanism for the winding of yarns, threads, and the like on spools with a reciprocating thread guide driven by a compound threaded spindle reciprocally driving a shoe follower with one segment riding in oppositely helical arranged grooves or threads crossing each other at least once and another segment of said shoe follower guiding it through parabolic or arcuate thread reversal segments of cross section different from that of the helical arranged threads.

Uited States Patent lnventor Rudolf Hohle-Halske am Stadtwald 30, Remscheid-Lennep, Germany Appl. No. 833,575 Filed June 16, 1969 Patented Oct. 12, 1971 Priority June 15, 1968 Germany P 17 60 659.6

TRAVERSE MECHANISM USEFUL IN TEXTILE MACHINES l 1 Claims, 9 Drawing Figs. U.S. CI 242/l58.3, 74/57, 242/43 Int. Cl B65h 57/28 Field of Search 242/43,

[56] References Cited UNITED STATES PATENTS 3,373,949 3/1968 Swallow 242/43 2,25 1,838 8/1941 Baker 74/57 3,334,829 8/1967 Fisher et al. 242/43 Primary Examiner-Leonard D. Christian Att0rneyJ0hnst0n, Root, OKeeffe, Keil, Thompson &

Shurtleff ABSTRACT: Traverse mechanism for the winding of yarns, threads, and the like on spools with a reciprocating thread guide driven by a compound threaded spindle reciprocally driving a shoe follower with one segment riding in oppositely helical arranged grooves or threads crossing each other at least once and another segment of said shoe follower guiding it through parabolic or arcuate thread reversal segments of cross section different from that of the helical arranged threads.

TRAVERSE MECHANISM ussrur. IN TExTrLE MACHINES INTRODUCTION For the traverse of threads, yarns, etc., during their winding on spools, traverse devices are known wherein the yarn guide is conducted between parallel rails or bars and is driven by a follower device. The follower and thread guide are moved back and forth by means of a rotating, compound threaded spindle having helical grooves or threads of opposite hand which cross at least once. In order to assure an effective guidance of the follower at the thread crossover points, the follower has a shuttlelike form. (See for example, German Pat. No. 422,401). In order to obviate difficulties arising especially at the thread crossovers by virtue of deflection of the follower, a spindle with a stepped thread composed of a wider, main helical groove and a narrower spiral groove in the base of the former has been proposed. In the outer, wider groove, a roller guide member functions especially at the thread reversal zones. The follower operates in the narrower groove, and this arrangement is supposed to achieve a faultless reversal of .the follower at the stroke ends. In consequence of the rolling friction in lieu of slide friction, the device is supposed to attain an increase of the traverse speed (See for example, German Pat. No. 1,155,041). Such a roller, however, has to absorb the thrust forces, which bring about direction reversal of the follower and yarn guide, which thrust forces are considerably increased with a higher rate of traverses. The thrust forces which are of particular concern occur between roller and roller axle during travel through the thread reversal zones. The higher the rate of traverses, the greater must be the diameter of the roller and of the roller axle in order to withstand the direction changing thrust forces. Otherwise, the roller and/or its axle can withstand the stresses only for a limited span of time because the thrust forces acting on the roller and its axle, on increase of rate of traverses, increase so severely that roller and axle soon become damaged through wear or deformation or breakage.

Furthermore, there are known guide mechanisms with a rotating, compound threaded spindle, in the circumference of which there is a stepped, helical thread or groove with an outer, wider groove course; The latter receives a follower of approximately diamond shaped contour, which is fitted, without play, exactly into the groove. In the inner groove course a usual-type controlshuttle guides the follower correctly through the crossing points of the helical grooves. The control shuttle is arranged coaxially to the guide member and independently rotatable with respect thereto. (See for example, US. Pat. Nos. 2,183,735 and 2,251,838). Such guide mechanisms are composed of a number of parts, which are subject to the same damaging efiects as above-described at the higher rates of traverses, whereby such mechanisms have little, if any, use in traverse mechanisms operating at relatively high rates of traverse.

Finally there has also been proposed a traverse device for spooling machines with compound threaded spindle, the helical grooves or threads cross each other and are in each case beveled toward the bottom. The follower is a diamond-type or shuttle-form shoe which carries the thread guide and has at its free end trapezoidal or triangular profile (See German Pat. No. 953,864).

The disadvantage of this arrangement lies essentially in its performance at higher traverse rates. The shoe of the follower is pressed out of the grooves in radial direction by the radial force components acting on it in the passage through the grooves. A spring used to hold the shoe in the helical grooves or threads is not capable at these rates of providing a sure tracking of the shoe in the groove bottom at the thread crossings, with the result that there is an increased wear and breakage of the follower.

DESCRIPTION OF THE INVENTION Underlying the invention, therefore, is the problem of developing a traverse device of the type described earlier, which, at a very high rate of traverses, conducts the follower surely and smoothly over the reversal and crossing places of a compound threaded spindle and avoids the defects and disadvantages of the devices known hitherto.

According to the invention, therefore, the follower consists of a single piece or of several pieces rigidly joined with one another. It has stepped segments corresponding to the stepped, thread-within-thread helical grooves of the spindle. The helical grooves are interconnected at their ends by an arcuate or parabolic, simple groove or thread, the latter providing the thread reversal of the spindle grooves. The narrower segment of the follower functions in the inner, narrower groove course, while its wider segment functions as a guide at the thread reversal zones in the simple groove or thread thereof. The wider segment contacts the groove wall only at the thread reversal zones. The guiding of the follower, accordingly, is taken over at the thread reversal curves of the spindle by the upper, wider part of the follower. The lower, narrower part of the follower does not touch the sidewalls of the groove at the thread reversal zones. The lower, narrower part of the follower functions exclusively in the helical arranged threads, and the upper, wider part of the follower preferably does not touch the sidewalls of the helical arranged threads.

Such an arrangement difi'ers from the known devices, in the first place, by the fact that the stepped, shuttle-type shoe follower is a rugged, preferably unitary structure adapted to withstand the considerably increased forces imparted thereto in the areas or zones of thread reversal on the spindle. These forces are absorbed solely by the thicker, more sturdy upper portion of the follower while the narrower, substantially weaker, lower part of the follower is not stressed at all at these thread reversal zones and runs therethrough entirely free. The narrower, lower part is actively engaged in the stepped, thread-within-thread helical arranged threads or grooves only in the guide interval between the reversal zones of the compound threaded roller and, in the process, is subjected to little stress. In this manner it is possible to achieve considerably higher, trouble-free traverse speeds. Furthermore, the useful life of the follower is considerably extended by this subdivision of functions, especially since the two parts of the shoe follower can be constructed in correspondence to the stresses encountered in their dilferent functions.

In order to produce a better guidance of the follower at the crossing points of the two counter-spiral threads, the lower, narrow part of the shoe follower has very nearly parallel sidewalls or slide flanks. An especially smooth travel of the shoe follower can be achieved, according to the invention, by longitudinally bowing its lower, narrower part in contours corresponding to the arcuate contours of the narrower, inner groove of the counter helical threads or grooves. Further, the flanges or sides of the upper wide part of the follower can be planar in the longitudinal middle portion. The follower thereby rides through the thread reversal zones with sliding contact only between points near opposite ends of said sides, whereby an especially smooth running is achieved. The helical threads or grooves have a substantially T-shaped cross section, and the upper, wider part of the follower runs in the helical grooves preferably at a slight clearance with the sides of the outer groove during the travel of the lower, narrower segment through the inner groove. Preferably there is little play between either part and their corresponding helical groove segments. Only in the reversal places does the upper, wider part take over the actual guidance of the shoe follower.

The selection of a suitable material which can readily be shaped into the above-mentioned forms and can withstand the stresses encountered permits a further increase of the traverse rate. Best results are achieved by making at least the thread contacting segments of the shoe follower of plastic, preferably of a polyamide. Since the plastics used are very light, the forces acting on the slide piece and the compound threaded roller remain within admissible limits, despite the high accelerations occurring at the reversal places. Further advantages of the polyamides are their good sliding properties, very good high-speed running properties, lo maintenance requirements, easy machinability and their low running noise.

In another embodiment of the invention the compound threaded spindle is composed of helical grooves of opposite hand of simple cross section, e.g., a simple square thread. The spindle has a larger diameter at the thread reversal zones to provide a longitudinally arcuate shoulder against which a side of the wide segment of the shoe follower rides through the thread reversal zone. This construction provides the equivalent of a thread-within-thread groove only immediately preceding and following each thread reversal point. This form is considerably simpler and more economically produced than a form in which the thread-within-thread groove extends throughout the helical threads or grooves.

DESCRIPTION OF THE DRAWINGS Several preferred embodiments of the invention are illustrated in the drawing wherein:

FIG. 1 is a plan view of the end fragment of a compound threaded spindle and shows the arcuate thread reversal zone at one end of said spindle;

FIG. 2 is a fragmentary transverse cross section of the helical grooves or threads and the shoe follower riding therein;

FIG. 3 is a fragmentary plan view of the compound threaded spindle at a crossing of the helical grooves or threads of opposite hand;

FIG. 4 is fragmentary, transverse cross section of the arcuate, thread-reversal groove taken on section plane 4-4 of FIG. 1;

FIGS. 5, 6 and 7, respectively, are a side elevation, end elevation and top plan view of one embodiment of a shoe follower;

FIG. 8 is a view similar to FIG. 1 of another embodiment of a compound threaded spindle and embodying simple helical grooves and thread-within-thread grooves only adjacent the thread reversal zones; and

FIG. 9 is a top plan view of another embodiment of a shoe follower.

Referring to the drawings, the compound threaded spindle l embodies a set of helical grooves or threads 2 and 2 of opposite hand in its circumference. The helical grooves 2 and 2' are thread-within-thread grooves having an outer, wider groove segment 2a and a narrower, inner groove segment 2b. The latter is a groove in the base of the outer groove 2a. The helical grooves 2 cross each other one or more times in the manner shown in FIG. 3.

At the respective ends of the compound threaded spindle 1 there is a thread reversal zone provided by the groove 3 interconnecting the ends of said helical grooves in a longitudinally parabolic or longitudinally arcuate curvature. The thread reversal grooves 3 are simple threads or grooves, i.e., of a simple profile such as a square thread. The width of the grooves 3 is at least equal to the width of the outer grooves 2a of the helical grooves 2. The depth of the grooves 3 are at least equal to the depth of the lower wall of the narrower groove segments Thus the composite of helical groves 2 and 2 and thread reversal grooves 3 provide an endless camming track for a shoe follower adapted to reciprocate back and forth along the spindle 1 as the latter rotates. The shoe follower 5 of FIGS. 5-7 comprises a shoe body portion and threaded shank 4. The latter is used to attach the shoe follower to a yarn traverse guide mechanism which guides the yarn back and forth as it is being wound on a spool. The shoe follower 5 preferably is a one-piece construction and preferably is made of an abrasionresistant polyarnide plastic such as Akulon (trademark). The two sidewalls 6 and 7 of the narrower shoe follower segment 5a have a contour corresponding to the contour 8 of the sidewalls of the narrower, inner groove segment 21:. The narrower segment 5a is longitudinally bowed in a curvature corresponding substantially to the curvature of the bottom wall of the narrower groove segment 2b and may be tapered or rounded at its respective ends with the major portion of said segment having a rectangular cross section of the type shown in FIG. 2.

The wider segment 5b of the shoe follower has a substantially oval shape in top plan view. It is longitudinally bowed in a curvature corresponding substantially to the curvature of the bottom wall of the wider groove segment 2a. The width of the wider segment 5b at the minor axis of its oval is preferably slightly less than the width of the wider groove segment 20 so that the shoe follower 5 runs freely and through the helical grooves 2. It is further dimensioned to run smoothly through the arcuate groove 3 of the thread reversal zones with little play therebetween.

The embodiment of FIG. 8 is a rotatable spindle 9 having end segments 9a of larger diameters than the main or middle segment 91;. The latter has in its cylindrical surface helical grooves of opposite hand, which grooves 20 and 2d are simple grooves such as the square thread type shown in FIG. 4 but having a width corresponding substantially to the width of the narrower segment 5a of the shoe follower. The shoe follower rides in the helical grooves 20 and 2d with only its narrower segment 5a in said grooves. At the thread reversal zones 10 at the respective ends of the spindle 9, the larger diameter ends 9a provide a longitudinally curved shoulder 11 against which one side of the wider segment 5b of the shoe follower rides through the thread reversal zones 10. The respective groove cross sections preceding and following the thread reversal zone 10 correspond to the cross sections shown in FIG. 2 with the circumference of spindle segment 91: being at the phantom line 13. The cross section at the thread reversal zone 10 corresponds to the simple thread cross section shown in FIG. 4.

The shoe follower 5' of FIG. 9 has its wider segment 5b in the form of an elongated oval as viewed in plan with, however, substantially flat or planar, longitudinal midportions 14 of its sidewalls. This shape is advantageous in that the portions of the sides of the wider segment 5b contact the parabolic or arcuate grooves at the thread reversal zones near the respective longitudinal ends of the wider segment. This shape provides especially good guidance of the shoe follower in the thread reversal zones 3 and/or 10.

It is thought that the invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous changes may be made in the fonn, construction and arrangement of the several parts without departing from the spirit or scope of the invention, or sacrificing any of is attendant advantages, the forms herein disclosed being preferred embodiments for the purpose of illustrating the invention.

The invention is hereby claimed as follows:

I. A traverse mechanism useful in devices for winding of yarns, threads and the like on spools which comprises a rotatable spindle having on its circumference helical grooves of opposite hand, said grooves crossing each other at intervals on said circumference, the ends of said helical grooves being interconnected by a longitudinally arcuate, thread reversal groove, said helical grooves having throughout their lengths a thread-within-thread composed of a wider, outer groove segment and a narrower, inner groove segment in the base of said wider groove segment, the arcuate groove of said thread reversal segments being of a depth equal to or greater than the total depth of said helical grooves and having a width in the base portion thereof greater than the width of said inner, narrower grooves, and a shoe follower riding in said grooves, said shoe follower having a narrower follower segment slidably engaged in and guided by the lower, narrower groove segment and a wider follower segment which is narrower than said wider groove segment and is adapted to travel through said wider groove segment with a small clearance between the sides of the wider groove segment and said wider follower segment, said wider follower segment having a width corresponding substantially to the width of said thread reversal grooves and being rigidly joined with said narrower segment, whereby said narrower follower segment rides through and is guided by the narrower groove segments as the shoe follower is traversing the rotating spindle and whereby the wider follower segment is engaged by and guided in only the thread reversal grooves.

2. A traverse mechanism as claimed in claim 1 wherein said narrower follower segment has substantially parallel sidewalls and said narrower groove segment is a square thread in the base of said wider groove segment.

3. A traverse mechanism as claimed in claim 1 wherein said narrower follower segment is longitudinally bowed in a contour corresponding to the arcuate contour of said narrow groove segment.

4i. A traverse mechanism as claimed in claim 1, wherein the sidewalls of the wider follower segment are substantially planar in the longitudinal midportion thereof.

5. A traverse mechanism as claimed in claim 1, wherein said helical grooves have an approximately T-shaped cross section and said segments of said follower have a matingly similar T- shaped cross section providing a small clearance between the sides of the wider groove segment and said wider follower segment.

6. A traverse mechanism as claimed in claim 1, wherein said segments of said follower are made of polyamide plastic.

7. A traverse mechanism useful in devices for winding of yarns, threads and the like on spools which comprises a rotatable spindle having a cylindrical midportion and end portions of larger diameter than said midportion, said midportion having on its circumference simple helical grooves of opposite hand, said grooves crossing each other at intervals on said circumference, the ends of said helical grooves being interconnected in thread reversal zones by a longitudinally arcuate, thread reversal shoulder located at the respective junctures of said midportion and said end portions of said spindle, each arcuate shoulder facing said midportion and defining a side of a longitudinal arcuate thread reversal groove extending through each thread reversal zone, said thread reversal grooves having a width in the base portion thereof greater than the width of said helical grooves and having a depth equal to or greater than the depth of said helical grooves, and a shoe follower riding in said grooves, said shoe follower having a narrower follower segment slidably engaged in and guided by said helical grooves and a wider follower segment adapted to travel across said midportion outside said helical grooves and adapted to engage said longitudinally arcuate shoulders upon reaching the respective ends of said midportion, whereby said narrower follower segment rides through and is guided by said helical groove as the shoe follower is traversing the rotating spindle, and whereby the wider follower segment is engaged by and guided through the thread reversal zones by said arcuate shoulders at the respective ends of said midportion.

8. A traverse mechanism as claimed in claim 7 wherein said narrower follower segment has substantially parallel sidewalls, and said helical grooves are square threads.

9. A traverse mechanism as claimed in claim 7 wherein said narrower follower segment is longitudinally bowed in a contour corresponding to the arcuate contour of said helical grooves 110. A traverse mechanism as claimed in claim 7, wherein the sidewalls of the wider follower segment are substantially planar in the longitudinal midportion thereof.

1]. A.traverse mechanism as claimed in claim 7, wherein said segments of said follower are made of polyamide plastic.

F UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,612,428 Dated October 12, 97

Inventor (s) Rudolf Hohle -Ha1ske It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

j First page, left-hand column, after 5] Patented Oct. 12,

1971", insert [73] Assignee Barmag Barmer Maschinenfabrik Aktiengesellschaft wuppertal, Germany Column line 53, "is" should read its Signed and sealed this 31st day of October 1972.

(SEAL) Attest:

EDWARD M.FLETCHER.JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

1. A traverse mechanism useful in devices for winding of yarns, threads and the like on spools which comprises a rotatable spindle having on its circumference helical grooves of opposite hand, said grooves crossing each other at intervals on said circumference, the ends of said helical grooves being interconnected by a longitudinally arcuate, thread reversal groove, said helical grooves having throughout their lengths a thread-within-thread composed of a wider, outer groove segment and a narrower, inner groove segment in the base of said wider groove segment, the arcuate groove of said thread reversal segments being of a depth equal to or greater than the total depth of said helical grooves and having a width in the base portion thereof greater than the width of said inner, narrower grooves, and a shoe follower riding in said grooves, said shoe follower having a narrower follower segment slidably engaged in and guided by the lower, narrower groove segment and a wider follower segment which is narrower than said wider groove segment and is adapted to travel through said wider groove segment with a small clearance between the sides of the wider groove segment and said wider follower segment, said wider follower segment having a width corresponding substantially to the width of said thread reversal grooves and being rigidly joined with said narrower segment, whereby said narrower follower segment rides through and is guided by the narrower groove segments as the shoe follower is traversing the rotating spindle and whereby the wider follower segment is engaged by and guided in only the thread reversal grooves.
 2. A traverse mechanism as claimed in claim 1 wherein said narrower follower segment has substantially parallel sidewalls and said narrower groove segment is a square thread in the base of said wider groove segment.
 3. A traverse mechanism as claimed in claim 1 wherein said narrower follower segment is longitudinally bowed in a contour corresponding to the arcuate contour of said narrow groove segment.
 4. A traverse mechanism as claimed in claim 1, wherein the sidewalls of the wider follower segment are substantially planar in the longitudinal midportion thereof.
 5. A traverse mechanism as claimed in claim 1, wherein said helical grooves have an approximately T-shaped cross section and said segments of said follower have a matingly similar T-shaped cross section providing a small clearance between the sides of the wider groove segment and said wider follower segment.
 6. A traverse mechanism as claimed in claim 1, wherein said segments of said follower are made of polyamide plastic.
 7. A traverse mechanism useful in devices for winding of yarns, threads and the like on spools which comprises a rotatable spindle having a cylindrical midportion and end portions of larger diameter than said midportion, said midportion having on its circumference simple helical grooves of opposite hand, said grooves crossing each other at intervals on said circumference, the ends of said helical grooves being interconnected in thread reversal zones by a longitudinally arcuate, thread reversal shoulder located at the respective junctures of said midportion and said end portions of said spindle, each arcuate shoulder facing said midportion and defining a side of a longitudinal arcuate thread reversal groove extending through each thread reversal zone, said thread reversal grooves having a width in the base portion thereof greater than the width of said helical grooves and having a depth equal to or greater tHan the depth of said helical grooves, and a shoe follower riding in said grooves, said shoe follower having a narrower follower segment slidably engaged in and guided by said helical grooves and a wider follower segment adapted to travel across said midportion outside said helical grooves and adapted to engage said longitudinally arcuate shoulders upon reaching the respective ends of said midportion, whereby said narrower follower segment rides through and is guided by said helical groove as the shoe follower is traversing the rotating spindle, and whereby the wider follower segment is engaged by and guided through the thread reversal zones by said arcuate shoulders at the respective ends of said midportion.
 8. A traverse mechanism as claimed in claim 7 wherein said narrower follower segment has substantially parallel sidewalls, and said helical grooves are square threads.
 9. A traverse mechanism as claimed in claim 7 wherein said narrower follower segment is longitudinally bowed in a contour corresponding to the arcuate contour of said helical grooves.
 10. A traverse mechanism as claimed in claim 7, wherein the sidewalls of the wider follower segment are substantially planar in the longitudinal midportion thereof.
 11. A traverse mechanism as claimed in claim 7, wherein said segments of said follower are made of polyamide plastic. 